Mechanism for angular adjustment of the bowsprit of a sailboat



Dec. 20, 1 932. I G, ROCKWOOD I 1,891,555

MECHANISM FOR ANGULAR ADJUSTMENT OF THE BOWSPRIT OF A SAILBOAT Filed June 10, 1932 2 Sheets-Sheet l Qeorye I Foc'k WW Dec. 20, 1932. L ROCKWOOD I 1,891,555

MECHANISM FOR ANGULAR ADJUSTMENT OF THE BOW-SPRIT OF A SAILBOAT Filed June 10, 1932 I 2 Sheets-Sheet 2 G905; a 11 0074 w??? 67 aq i nvaqd' Patented Dec. 20, 1932 UNITED STATES PATENT oFFICE I GEORGE I. ROCKWOOD, OF WORCESTER, MASSACHUSETTS Application filed June 10,

This invention relatesto small sailboats having a single mast and rigged with 'a mainsail and jib. 'In such boats it is customary to mount the jib on a rope or ib stay fastened at its forward lower end to the front end of a bowspritand at its upper end to a point on the' maininast above the limits of travel of the mainsail gaff.

It is also customary to rigidly secure the bowsprit to the hull, so that the jib stay also acts to hold the mast in the boat and to oppose rearward air' pressure against sails hung thereon.

It is the general object of my invention to improve the manner of positioning the jib,

to the end that the jib may be automatically maintained at the most desirable angle for effective operation.

To the accomplishment of this object, I preferably provide a bowsprit which is mounted to swing or swivel about a bearing adjacent to the foot of the mainmast.

I also provide means to permit shifting of the jib when tacking, and means for guiding and securing the jib sheet during sailing operations.

My invention further relates to arrangements and combinations of parts which will be hereinafter described and more'particularly pointed out in the appended claims.

A preferred form of the invention is shown in the drawings, in which a Fig. 1 is a side elevation of a sail boat having my invention applied thereto; a Fig. 2 is an enlarged plan view of the forward portion of the boat; 3

Fig. 3 is a detail plan View of a sheave to be described;

Fig. 4 is a side elevation of certain parts, looking in the direction of the arrow l in F i 3 but showing the parts in a somewhat difierent position;

Fig. 5 is a view similar to Fig. 2 but showing the boat on the opposite tack;

Fig. 6 is a detail view similar to F g. 1 and illustrating the shifting of the jib aftertaclring, and i Fig. 7 is a detail plan view showing the relation of the jib sheets to the main-boom. {Referring to the drawings, I have shown 1932 Serial no. 16,510.

a small sailboat B having a mainmast 10 at the bow of theboatand-also having the usual boom 11 and gafi 12 on which a mainsail M is mounted. The boat B is'also provided with a jib J mounted on a jib stay 13 5 which has its lower endattached to the forward end of a bowsprit' 14. The upper end of the jib stay 13 is secured to the'mainmast at a point 15, and the'jib is provided with a relativelylight jib boom 16, called by sailors a club.

The mainsail boom 11, instead of'directly engaging the mainmast 10 in the usual manner, is provided with a yoke 20 pivoted at 21 to opposite points on asheave 22,? rotatable about a fixed pivot 23 justrearwardof the mainmast 10. The sheave 22 is. provided with an elongated segmental slot 25 through which the mainmastextends, which slot permits the sheave and boom to havea free swinging movement over the fullest angular range which the mainsail can use.

The bowsprit 14 is provided with a pivot shaft 30 having bearings 31 and 32 fixed to the bow of the boat The shaft 30 is pref- 5 erably mounted at such an angle that an up-' ward extension of its center linewould sub: stantially pass through the point 15 where the peak of the jib is secured to the mainmast. WVith this construction; thejib-stay 13 of the jib J is held taut in every angular position of the bowsprit and thus actsas the usual mast stay.

The rear portion of the bow'sprit 14 is enlarged as indicated in Fig.2 to provide a 3 second sheave-like member 34', and the member 34 is connected by ropes 35 and 36 to the sheave 22 previously described, the

sheaves being suitably grooved in their edge portions to receive and retain the ropes 35 d 3 I o v The ropes 35 and 36 may be formed as parts of a singlecontinuous rope wrapped about the two sheaves 22 and 34 and fastenedthere? to at points 37 and 38 on the circumferences of the sheaves, which points are farthest apart when the boom 11 and b owsprit l l are on the center line of the boat.

A guide-rod or travelerl lO is mounted on 1 the sheave portion 34 of the bowsprit 14 and .9

forms a guide for a sleeve 41 connected by a rope or chain 42 to a sleeve 43 loosely mounted on the jib boom or club 16. The bowsprit 14 is provided with a brace or bob-stay 45 extending to and pivoted at the lower end of the shaft 30 and substantially stiffening the bowsprit construction.

The jib sheet 50, instead of being attached directly to the hull of the boat as is customary, is carried rearward to a block or guide 53 on the mainsail boom 11, and then forward to a fixed guide-pulley or block 54 just aft of the sheave 2-2, from which it may extend rearward to a cleat 55 conveniently positioned for the navigator. It is desirable that the sheet 50 be so adjusted that the jib boom 01' club16 will assume substantially the relative position indicated in Fig. 2. The jib preferably extends substantially aft of the mainrnast, for reasons which form no part of my present invention.

IVith the parts connected as shown in Fig. 2, it will be clear that any swinging movement of the mainsail boom 11 will be accompanied by a corresponding swinging movement of the bowsprit 14:, and that these parts will remain in substantially parallel relation in every position of the boom and bowsprit. The jib is correspondingly adjusted without further attention to the length of the jib sheet,and the relative angular position of the jib and mainsail also remains substantially unchanged during the usual adjustments of the mainsail sheet.

The guidance of the jib-sheet 50 through the block 53 on the mainsail boom 11 and thence to the block 54: on the hull of the boat causes an automatic shortening of the jib sheet'as the boom swings out, which is just sufiicient to ofiset the slackness which would otherwise occur if the jib sheet 50 were attached direct to the mainsail boom 11. The jib 'J is thus automatically maintained at its most effective angle as the boom is swung to different desired positions to accommodate shifting winds or courses, andthe sailing qualities of the boat are thereby much improved- I 'In order to be able to handle the jib on either tack, I provide the usual second sheet 51 (Fig. 2) which is carried around forward of themainmast 10 and is then led back to the block 53 on the boom 11, thence to the block 54 on the forward deck and to the fixed cleat 55. This second sheet 51 is loose and inoperative when the parts are in, the position shown in Fig. 2 but becomes operative when the parts are shifted to the position shown in Fig. 5. l V

As the boom is swung over on the opposite tack, the jib boom or club 16 is slipped forward in its rings, as indicated in Fig. 6, until it clears the mast 10, after which it is drawn rearward by the tightening of the sheet 51.

The connection of the club 16 to the traveler 40 by the rope or chain 42 not only stiffens the jib but also tends to prevent excessive upward swinging movement of the mainsail boom 11. It will be noted by reference to Fig. 1, that the rear end 60 of the jib boom or club 16 is held from upward movement by the connection of the club to the bowsprit 14 and to the traveler 40. Consequently when the boom 11 tends to swing upward at an excessive angle, as occasionally happens due to rolling of the boat when going before the wind, the sheet 50 exerts a downward pull and counteracts the tendency of the boom to swing upward.

IVhile it is usually desirable that the bowsprit and boom maintain a substantially parallel relation, it will be evident that by varying the relative size of the sheaves 22 and 34, the angle of movement of the bow sprit may be made either greater or less than the angle of movement of the boom.

The sailing qualities of a boat will be much improved by the use of my improved auto matically adjustable bowsprit, by which the jib is maintained at the most effective angle in every position of the mainsail.

Having thus described my invention and the advantages thereof, I do not wish to be limited to the details herein disclosed, other-- wise than as set forth in the claims, but what I claim is 2- 1. In a sailboat having a mainmast, a mainsail, a boom for said sail, a jib and a jib-stay, in combintion, a bowsprit to which the forward lower end of the jib-stay'is secured, and means to move said bowsprit and mainsail boom simultaneously.

2. In a sailboat having a mainmast, a mainsail, a boom for said sail, a jib and a jib stay, in combintion, a bowsprit to which the forward lower end of the jib-stay is secured, and means to move saidbowsprit and mainsail boom simultaneously about separate but adjacent axes.

'3. In a sailboat having a mainmast, a mainsail, a boom for said sail, a jib and a jib-stay, in combination, a bowsprit to which the forward lower end of said jib-stay is secured, and means to move said bowsprit and mainsail boom simultaneously and to thereby maintain said bowsprit and boom in substantially parallel relation in all positions connections between said bowsprit and said mainsail boom through which swinging movement of the boom effects simultaneous swinging movement of thebowsprit and in the same angular direction;

5. In a sailboat having a ina1nmast,amainsail, a boom for said sail, a jib and a jibstay, in combination, a bowsprit to which the forward lower end of said jib-stay is secured, a pivot bearing for said bowsprit, and connections between said bowsprit and said mainsail boom through which swinging movement of the boom effects simultaneous swinging movement of the bowsprit and maintains said bowsprit and boom substantially parallel in all positions of said boom.

6. In a sailboat having a mainmast, a mainsail, a boom for said sail, a jib and a jib-stay, in combination, a bows rit to which the forward lower end of said jib-stay is secured, the upper end of said j ib-stay being connected to saidmainmast, a pivot bearing for said bowsprit having its extended center line passing substantially through the point of connection of said jib-stay to said mainmast, and connections between said bowsprit and said mainsail boom through which, swinging movement of the boom effects simultaneous swinging movement of the bowsprit.

7. In a sailboat having a mainmast, a mainsail, a boom for said sail, a jib and a jibstay, in combination, a bowsprit to which the forward lower end of said j ib-stay is secured, a sheave to which said mainsail boom is connected, a sheave formed integral with said bowsprit, and flexible connections between said sheaves by which swinging movement of the mainsail boom effects simultaneous swinging movement of the bowsprit.

8. In a sailboat having a mainmast, a mainsail, a boom for said sail, a jib and a jibstay, in combination, a bowsprit to which the forward lower end of said jib-stay is secured, a sheave to which said mainsail boom is connected for vertical swinging movements, a sheave formed integral with said bowsprit, and flexible connections between said sheaves by which swinging movement of the mainsail boom effects simultaneous swinging movement of the bowsprit.

9. In a sailboat having a mainmast, a mainsail, a boom for said sail, a jib'rand a jibstay, in combination, a bowsprit to which the forward lower end of said jib-stayis secured, a sheave to which said mainsail boom is connected, a sheave formed integral with said bowsprit, and flexible connections between said sheaves by which swinging movement of the mainsail boom effects simultaneous swinging movement of the bowsprit, said first sheave having an elongated segmental slot to provide clearance for said mainmast.

10. In a sailboat having a mainmast, a mainsail, a boom for said sail, a jib and a jibstay, in combination, a bowsprit to which the forward lower end of the jib-stay is secured, means to move said bowsprit and mainsail boom simultaneously, and a sheet for said jib, said jib-sheet extending substantially rearward to a point of guidance on said mainsail boom, and thence forward to a fixed point on the deck adjacent but rearward of the axis of swin ing movement of said boom.

11. In a sail oat having a mainmast, a mainsail, aboom for said sail, a jib and a jib-stay, in combination, a bowsprit to which the forward lower end of the jib-stay is secured, means to move said bowsprit and mainsail boom simultaneously, and a sheet for said jib, said jib-sheet extending substantially rearward to a point of guidance on said mainsail boom, and thence forward to a fixed point on the deck adjacent but rearward of the axis of swin ing movement of said boom, said sheet shding through its point of guidance on said boom as the boom swings out-board and thereb maintaining a substantially uniform angu ar relation between said mainsail and jib.

In testimony whereof I have hereunto affixed my signature.

GEORGE I. ROCKWOOD. 

